Namık Kemal University

Faculty of Agriculture

Department of Animal Science

VIth International Balkan Animal

Conference

BALNIMALCON 2013

Fulltext Notes

3-5 October 2013

Tekirdag / Turkey

EFFECT OF RAPESEED MEAL (RSM) FED ON FATTENİNG LAMBS

MARİN YOSSİFOV* AND LAZAR KOZELOV

Institute of Animal Science, Kostinbrod, Bulgaria, 2232

*Corresponding author:

Phone: +359878624899

Fax: +35972166029

E-mail address: m_vet@abv.bg

SUMMARY

Objectives were to evaluate the chemical composition and effects of Rapeseed meal (RM) on feed intake, growth and gain

efficiency of fattening Synthetic Bulgarian Dairy Population (SBDP) lambs. Thirty-two lambs (16.71±2.35 kg initial BW and

59 days of age) were stratified by weight and sex and randomly alloocatted to one of 2 pens and assigned to treatments (n=2).

Diets were formulated to meet CP, energy, calcium and phosphorus requirements. Treatments were iso-nitrogenous, iso-caloric

and with balanced Ca: P ratios. The basal diet consisted of roughage - Meadow Hay (MH), triticale, corn grains and a trace

vitamin-mineral supplement. Protein source was 27.19% RM vs. 26.33% Sunflower Meal (SFM) on a diet basis (16 lambs.diet-

1). Feed intake was monitored daily. Body weight was monitored every 2 weeks. After 82-d feeding trail were determined feed

intake, DMI, average daily gain and gain efficiency. Final BW and Average Daily Gain (ADG) were significant affected by

RSM (p<0.01) treatments. Total DMI was lower for lambs fed RM diet as compared with lambs fed SFM diet. Results indicated

that RM is a viable feedstuff for fattening lambs without any compromise in monitored performance.

Key words: Rapeseed Meal, Average Daily Gain, Dry Matter Intake, Feed Efficiency, Lamb Performance

INTRODUCTİON

Canola seeds contain approximately 20 % protein and 38 % fat (Kercher et al., 1990a,b), therefore,

they could serve as both protein and energy sources for livestock. Rapeseed meal is a by- product of the

biofuel industries after oil extraction from rape. It is the second most widely traded protein forage (Ash

and Dohlman, 2006; www.canolacouncil.org). RSM has a high content (Näsi and Siljander-Rasi,

1991; Roth-Maier et al., 2004) of crude protein (CP= 30 – 40 %), crude fiber (CF= 12 %, Sauvant et

al., 2004), neutral detergent fibers (NDF= 20 - 35 %, www.canolacouncin.org), ether extract (EE= 0.2

– 2 %, www.canolacouncin.org). The extent of degradability varied 65.8% – 66.8% (На et al., 1984;

Woods et al., 2003), influenced by animal variation, other dietary ingredients and feed processing. All

these characteristics made RSM well suited for ruminant diets, especially because of relatively low

NDF:ADF ratio may actually benefit their feeding. Some of the limiting factors are nutrient composition

and so named anti-nutritional factors (ANF). The group of ANF and a few minor components with anti-

nutritive effects (Bell, 1993) included glucosinolates, eruc acid, tannins, sinapine, phitic acid, phenols.

Ruminants are less affected by these substances in RSM than nonruminants, but recommended optimal

dietary inclusion levels in lamb’ total rations are only 10 % (Goopfert et al., 2006).

Canola meal’ nutrient composition may be influenced by environmental conditions during the growing

of the crop, by harvest conditions and to a minor extent by cultivar and processing of the seeds and meal.

Few scientific reports are available that evaluate RSM in lamb-finishing rations and most of them

(Hill et al., 1990; Маbon et al., 2000; Iliev et al., 2008) found negative effect on lamb consumption

and performance. Some authors not found negative effect on performance (Vincent et al., 1990; Hill et

al., 1991; Liu et al., 1998), contrary to Wiese et al., 2003, who published improved DMI and ADG (+

14 %).

The objective of the experiment reported herein was to formulate lamb-finishing diets at higher

inclusion levels of RSM. Thus, we evaluate the effect of 27 % dietary RSM inclusion exceeded triple

standard recommendations for weaned lambs on diet utilisation and performance (DMI, ADG, G:F,

nutrient conversion (DM, CP, PDI, FUG) per 1 kg gain).

MATERİALS AND METHODS

EXPERİMENTAL ANİMALS. 87-d feeding trail (7-d preparatory and 82-d experimental period) was

conducted at the Institute of Animal Science, Kostinbrod, BG, using thirty two lambs (average initial

BW 16.71 ± 2.35 kg, 59-d of age) of Synthetic Bulgarian Dairy Population (SBDP). They were weaned

(59-d of age) and randomly allocated (by weight, sex, day of birth, type of litter) into two dietary

treatments (n=16): control diet (CD) with SFM and experimental diet (ED) with RSM. To minimize

variation due to drinking, feeding, and defecation, lambs were weighed full on the morning to obtain

initial (days 0, 1) and final (days 81, 82) live weights in two consecutive days. Based on IBW lambs

were sorted for assignment to one of two treatment diets (n=16). Throughout the experimental period

(82-d), lambs were weighed (without withdrawal of feed or water) twice a month before morning

replenishment of feed.

DİETARY TREATMENTS. Nutrients in the ration ingredients were chemically measured (table 1) and

formulating the total diets (table 2). Daily rations were consisted of 36 % meadow hay (MH) and 64 %

Table 1. Chemical composition of feedstuffs (%)1

MH SFM RSM Triticale Corn

MH

- M

eado

w h

ay,

SF

M-

Sun

flo

wer

mea

l, R

SM

- R

apes

eed

mea

l.

1 A

s D

M b

asis

(ex

cep

t D

M).

Dry matter 84.74 86.32 87.35 83.57 81.66

Crude protein 8.46 37.24 36.35 12.04 7.38

Ether extract 1.09 0.82 3.07 1.44 2.71

Crude fiber 35.78 20.84 13.70 1.44 3.17

Ash 5.80 7.50 7.29 3.72 1.04

Ca 0.34 0.44 0.70 0.06 0.06

P 0.16 1.21 1.03 0.35 0.21

concentrate mixture (as-fed basis) and was formulated to meet and exceed all nutrient requirements of

fattening lambs (NRC, 2007). Concentrate mixtures containing RSM and SFM, as a protein source,

were formulated to be iso-caloric, iso-nitrogenous and aligned in Ca and P. Diets containing meadow

hay, supplement, corn, triticale and different protein source – 26 % sunflower meal (SFM) vs. 27 %

rapeseed meal (RSM).

Table 2. Chemical composition and feeding value of diets based on either rapeseed or sunflower meal

Item SFM- based

diet

RSM- based

diet

PD

I- P

rote

in t

ruly

dig

esti

ble

in

sm

all

inte

stin

es, B

PR

- B

alan

ce o

f p

rote

in i

n r

um

en, F

UG

- F

eed

unit

s fo

r g

ain

1 A

s D

M b

asis

(ex

cept

DM

).

2 L

imes

tone

+ S

alt

+ C

aHP

O4.2

H2

O +

Vit

amin

-min

eral

pre

mix

(P

rovid

ed t

he

foll

ow

ing

per

kg

of

die

t: M

g-6

0.0

mg

, F

e-1

.3 c

op

per

-1.0

mg

, I-

1.6

mg,

Zn

-60

.0 m

g,

Co

-1.0

mg

, V

it.A

-5000

IU,

Vit

.D-2

000

IU

, V

it.E

-10

.0 m

g).

3 A

cco

rdin

g t

o B

ulg

aria

n f

eed e

val

uat

ion s

yst

em.

4 O

ur

ow

n d

ata

(Yo

ssif

ov

et

al.,

20

11).

5 A

s fe

d b

asis

.

Components1 (%):

Meadow hay 36.64 36.25

Rapeseed meal - 27.19

Sunflower

meal 26.33 -

Triticale 17.17 16.99

Supplement2 2.69 2.58

Corn 17.17 16.99

Chemical composition4 (g.kg-1):

Dry matter 738.90 749.20

Crude protein 142.00 143.00

Ether extract 11.60 17.10

Crude fiber 172.80 157.70

Ash 40.15 40.40

Ca, % 0.99 0.99

P, % 0.44 0.45

Feeding value4,5(g.kg-1)

PDI 87.16 87.75

BPR 22.28 21.70

FUG3 0.89 0.91

The supplement provided Ca (limestone) and vitamin-mineral mix (manganese- 60.0 mg, iron- 1.3 mg,

copper- 1.0 mg, iodine- 1.6 mg, zinc- 60.0 mg, cobalt- 1.0 mg.Vit.A- 5000IU, Vit.D- 2000 IU, Vit.E-

10.0 mg). The diets were offered twice daily - concentrate mixture (offered at 8.00 and 14.00 h) and

roughage (offered at 10.00 and 16:00 h) were fed separately throughout the experimental period. Feed

intake was adjusted weekly to allow an excess of 5 % of their anticipated intake expressed as fed basis.

Animals were provided ad libitum access to feed and water throughout the study.

SAMPLE COLLECTİON AND ANALYSES. Diet ingredients were sampled monthly and composited for

analysis. The residia were collected and weighed daily and analized twice a month. Samples were

analyzed for DM by drying in a forced-air oven at 65oC for 48 h and then 105oC. Dried feed samples

were ground to pass through a 1-mm screen and analyzed for Crude Protein (CP) (Kjeldahl Nx6.25),

Ether Extract (EE), Crude Fibers (CF), Ash, Calcium and Phosphorus (Sandev, 1979; АOAC, 2002).

PARAMETERS. Dry matter intake (DMI) was calculated as (feed delivered /residia collected) x % DM

of the diet fed. Weight gains for the lambs in each pen were averaged and total pen feed intake was

halved so that the experimental observations were the data for pens expressed as per lamb basis. Average

daily gain (ADG), DMI, feed conversion rate and gain:feed (G:F) were determined in each 15-d period

which animal weights were obtained (per group).

STATİSTİCAL ANALYSİS. Feed intake and DMI (average per lamb), average daily gain, gain efficiency

and other parameters were analyzed using MS Office 2007 and Student’ t-test.

RESULTS AND DİSCUSSİON

DIET COMPOSITION. Chemical composition of feedstuffs is presented in table 1. Tested protein forage

(RSM) was lower in protein content (36.35 %) than SFM. Our results for CP % are similar to those

reported by NewkirkPresntPpt.pdf and www.canolacouncil.org, but higher than those found by

Hougen (1983); Homolka (1996) and NRC (2001). Significantly lower levels of CP were noted by Bell

et al. (1991); Feedbase (2008) and www.countrywidefarmers.co.uk. It is worth noting the difference

in actual values obtained for fat content – among the studied feedstuffs RSM has highest levels of EE

(3.07 %). The results are actual consequence of the technological process. Similar values were reported

by Bell et al. (1991) and www.countrywidefarmers.co.uk. Contrary, significantly lower values were

found by NewkirkPresntPpt.pdf and www.canolacouncil.org. Other (MAFF (1990); Homolka

(1996) and Feedbase (2008)) reported higher values. RSM was particularly poor in CF (13.70 %). The

observed values corresponded to these reported by Bell et al. (1991), but were lower than those found

by Homolka (1996); NRC (2001) and Feedbase (2008).

The compound feeds (table 2) were iso- nitrogenous in average 14 % CP and with similar DM basis

– 74 and 75 %, for CD and ED, respectively. CD was lower (11.60 g.kg-1 DM) in EE levels than ED

(17.10 g.kg-1 DM) with 47 %. CF content was lower in ED (- 9 %) than CD as a consequence of CF

content in protein forage (34 % lower in RSM). The found values of ash, Ca and P were equivalent

among the diets – 4, 0.99 and 0.45 %, respectively.

Chemical analysis of feedstuffs and diets result in a good-quality basis for consecutive feeding value

(Yossifov et al., 2011). Energy and protein nutritive values were estimated (table 2) according to

Bulgarian Feed Evaluation System (Todorov, 1995). Protein truly digestible in small intestines (PDI),

balance of protein in rumen (BPR) and feed units for gain (FUG) practically were the same among the

groups – 87, 22 g.kg-1 and 0.9 units, respectively. The data of diets’ chemical analysis and feeding value

described RSM as representative oilseed meals and excellent source of protein and energy.

INTAKE. Results about average daily intake of dry matter (DMI) and nutrient ingredients are presented

in table 3. Including RSM in ED didn’t result in any changes in DMI of concentrate mixture – 768.25

g.d-1 vs. 773.98 g.d-1 for CD (- 0.74 %). Contrary, hay and total diet intake were depressed in ED with

13 and 5 %. Differences in average daily intake of nutrient ingredients from total diet: CP (- 5 %), PDI

(- 5 %), BPR (- 9 %), EE (+45 %), CF (- 19 %), FUG (- 2 %), Ash (- 8 %), Ca (+ 13 %) and P (- 0.1 %)

among the groups varied.

Table 3: Average daily intake of DM and nutrient ingredients a

Item

Concentrate

mixture: Roughage: Total ration:

DM

- d

ry m

atte

r, C

P-

cru

de

pro

tein

, E

E-

ether

extr

act,

CF

- cr

ud

e fi

ber

, C

a- c

alci

um

, P

- pho

spho

rus,

F

UG

- fe

ed

unit

s fo

r g

ain,

PD

I -

pro

tein

tru

ly d

iges

tib

le i

n s

mal

l in

test

ines

, B

PR

- b

alan

ce o

f p

rote

in i

n r

um

en.

a A

ll v

alu

es a

re a

s d

ry m

atte

r b

asis

(ex

cept

dry

mat

ter)

;

b W

ith

ou

t p

rem

ix

SFM RSM SFM RSM SFM RSM

Chemical composition (DM basis %)

DM 773.98 768.25 378.31 327.31 1152.29 1095.56

СP 165.52 159.46 32.01 27.49 197.52 186.95

EE 11.15 18.53 4.12 3.57 15.27 22.10

СF 84.52 59.20 135.36 117.11 219.88 176.31

Ash 31.52 29.93 21.94 18.98 53.21 48.92

Ca 11.22 13.00 1.29 1.11 12.50 14.11

P 6.14 6.21 0.62 0.53 6.75 6.74

Feeding value (DM basis %):

FUG 0.99 1.00 0.21 0.18 1.20 1.18

PDI 94.80 91.92 24.21 20.95 119.02 112.87

BPR 41.52 37.63 -6.51 -5.63 35.02 32.00

.

As fed basis (fig. 1) the concentrate mixture average daily consumption varied in 10 g.d-1. Contrary,

hay and total ration intake as fed basis in ED – with 13 and 5 %, respectively. So, RSM at 27 % dietary

inclusion was not high enough to depress significantly intake. The intake data obtained by us

corresponding with results, published by Hill et al., 1990; Liu et al., 1998; Mandiki et al., 1999 and

Iliev et al., 2008.

Figure 1. Average daily intake (ADI) of concentrate mixture, roughage and total ration as fed basis

Conversely, Lardy et al. (1994) and Wiese et al. (2003) observed improved feed consumption in

animals, fed RSM- based diets.

ANIMAL PERFORMANCE. Animal performance is shown in table 4. In SFM- based group, lambs gained

slower. Animals fed other protein supplement (RSM) did higher rates of gain. Final BW was higher in

lambs fed ED (35.52 kg) then those fed CD (31.58 kg). The difference was significant (12.48 %) and

statistically proven (p<0.01).

Table 4. Average daily gain (ADG) and Gain efficiency (G:F) of fattening lambs fed different protein

source (SFM vs. RSM) /n=16, x ± SD/

Item SFM RSM

SF

M-

sun

flo

wer

mea

l, R

SM

– r

apes

eed m

eal,

BW

- bo

dy w

eigh

t, A

DG

- av

erag

e

dai

ly g

ain,

DM

I- d

ry m

atte

r in

tak

e, G

:F-

gai

n/f

ora

ge.

* M

ean

s w

ithin

ro

ws

hav

ing

su

per

scri

pt

are

sig

nif

ican

tly

dif

fere

nt

at p

<0.0

1.

Growth performance:

Initial BW kg 16.78 ± 2.39 16.64 ± 2.38

% 100 99.17

Final BW kg 31.58a ± 5.39 35.52a ± 5.59

% 100 112.48

ADG kg.day-1 0.16a ± 0.04 0.19a ± 0.04

% 100 118.75

Gain efficiency:

G:F

(ADG:DMI)

per unit 0.180 0.231

% 100 128.33

Weight gain and feed efficiency of lambs fed RSM- based diet were better than those fed SFM. Average

daily gain (ADG) averaged 160 and 190 g.d-1 for the CD and ED. The differences (18.75 %) among

RR RR

CC CC

TRTR TRTR

Group, fed with SFM-based diet Group, fed with RSM-based diet

98.75 %

98.75 %100 %100 %

86.52 %

86.52 %

100 %100 %

94.74 %94.74 %100 %100 %

As fe

d ba

sis

treatments were statistically significant (p<0.01). The corresponding values for gain efficiency,

expressed as G:F ratio, were 0.18 and 0.23, respectively (28.33 %).

Figure 2.

Feed efficiency (kg/kg gain) of fattening lambs fed SFM vs. RSM as protein

source

The ADG and G:F data of lambs in the current study were comparable to those reported by other

researchers. These results agree only with Weise et al. (2003). Contrary, some authors (Hill et al., 1990;

Mabon et al., 1999 and Iliev et al., 2008) published negative effect and other (Vincent et al., 1990;

Mandiki et al., 1999) found no effect.

Feed efficiency (fig. 2) was expressed as DMI (6.39 vs. 4.74 kg.kg-1), CP (1.09 vs. 0.81 kg.kg-

1), PDI (0.66 vs. 0.49 kg.kg-1), BPR (0.20 vs. 0.14 kg.kg-1), energy as FUG (6.65 vs. 5.11 kg.kg-1) per 1

kg gain. It was observed benefits from RSM- based diet in conversion of all chosen parameters (- 26,

26, 26, 29 and 23 %) per 1 kg gain compared with SFM- based diet.

The results of this study indicate that RSM can completely replace sunflower meal and a portion of

corn in the supplement and up to 27 % of dietary DM when feeding fattening lambs without any

compromise to lamb performance. The chemical composition data confirm that our product was within

the middle range of the reported values. The lack of detectable negative effect among treatments and the

better performance of experimental diet may be attributed to the inclusion of relatively high level of

RSM.

CONCLUSIONS

ξ Data obtained on the chemical composition of RSM were: DM - 87.35%; CP - 363.50 g.kg-1, EE -

30.70 g.kg-1; CF - 137.00 g.kg-1, Ash - 72.90 g.kg-1, Ca - 7.00 g.kg-1 and P - 10.30 g.kg-1 (as DM basis);

ξ Feed intake, estimated as average daily consumption of total ration per group, was decreased by RMS-

based diet with 5 %;

ξ Growth performance, established as final BW and average daily gain, load to significant differences

(p<0.01), higher for lambs received RSM- based diet (+ 12.48 and 18.75 %, respectively);

ξ Gain efficiency, expressed as G:F ratio, was 28.33 % higher for lambs fed RSM- based diet;

ξ Feed efficiency observed benefits from RSM- based diet in conversion of DMI, CP, PDI, BPR, FUG

(- 26, 26, 26, 29 and 23 %) per 1 kg gain compared with SFM- based diet.

0

1

2

3

4

5

6

7

DM CP PDI BPR FUG

SFM-based diet RSM-based diet

- 26 %

- 26 %

- 26 %

- 23 %

- 29 %

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